Research proposed herein by the American Dental Association Health Foundation (ADAHF) is intended to (1) provide new and improved biocompatible dental restorative materials as alternatives to dental amalgam; (2) develop a coating that will improve the efficacy of currently-placed amalgam restorations; (3) develop appropriate clinical instrumentation, procedures and guidelines for the successful use of these materials; and (4) develop innovating materials processing strategies and facilitate the transfer of these technologies to dental manufacturers and practicing dentists. This interrelated, multidisciplinary research is responsive to the PHS "Healthy People 2000" agenda; to the goals of Specialized Materials Science Research Centers, as stated in RFA DE-93-001; and to a major initiative by the National Institute of Dental Research to develop improved, economical and biocompatible alternatives to dental amalgam. In testimony before the House Appropriations Subcommittee in March 1993, Dr. Harald Loe reported the development of a "prototype mercury-free dental amalgam." The material to which he referred was invented by scientists at the National Institute of Standards and Technology (NIST) and its viability was demonstrated in a pilot project of the ADAHF's Center of Excellence for Materials Science Research. Some phases of the material's further development are now being conducted by Center staff in collaboration with NIST scientists, and continued work on this project is proposed in this application (Consolidation and Delivery Methods for a Metallic Direct- filling Amalgam Alternative). It is also proposed that the Center research team that developed glass-ceramic inserts to improve the properties of composite restorations, introduced commercially in 1991, investigate other applications of the glass-ceramic material (Glass- ceramic Restorative Materials). It is proposed that current Center research to develop protective tooth coatings be extended to the development of polymeric coatings adhesive not only to crown and root surfaces but also to restorations of amalgam and its alternative materials (Polymers for Preventive Coatings and Margin Repairs); that current Center work on expanding monomers be redirected toward a general investigation of stress reduction in composite restorations (Reduction of Polymerization Shrinkage and Stress); and that the "synthetic dentin" being developed by Center staff be further explored for a variety of dental and biocompatability testing applications (Novel Adhesive Cariostatic Cements).